scholarly journals Direct assessment of the acidity of individual surface hydroxyls

Nature ◽  
2021 ◽  
Vol 592 (7856) ◽  
pp. 722-725
Author(s):  
Margareta Wagner ◽  
Bernd Meyer ◽  
Martin Setvin ◽  
Michael Schmid ◽  
Ulrike Diebold
Keyword(s):  
Direct Assessment ◽  
Surface Hydroxyls

Assessment of Cognitive Load in Multimedia Learning Using Dual-Task Methodology

2002 ◽  
Vol 49 (2) ◽  
pp. 109-119 ◽  
Author(s):  
Roland Brünken ◽  
Susan Steinbacher ◽  
Jan L. Plass ◽  
Detlev Leutner
Keyword(s):  
Cognitive Load ◽  
Dual Task ◽  
Cognitive Load Theory ◽  
Multimedia Learning ◽  
Learning Systems ◽  
Learning Materials ◽  
New Approach ◽  
Direct Assessment ◽  
Load Theory ◽  
Audiovisual Presentation

Abstract. In two pilot experiments, a new approach for the direct assessment of cognitive load during multimedia learning was tested that uses dual-task methodology. Using this approach, we obtained the same pattern of cognitive load as predicted by cognitive load theory when applied to multimedia learning: The audiovisual presentation of text-based and picture-based learning materials induced less cognitive load than the visual-only presentation of the same material. The findings confirm the utility of dual-task methodology as a promising approach for the assessment of cognitive load induced by complex multimedia learning systems.

Development of an IRT-based Direct Assessment of Preschool Science

2008 ◽  
Author(s):  
Daryl B. Greenfield ◽  
Ximena Dominguez ◽  
Janna Marie Fuccillo ◽  
Michelle Filomena Maier ◽  
Ariela Caren Greenberg
Keyword(s):  
Direct Assessment ◽  
Preschool Science

Direct Assessment of Functional Status Scale

1989 ◽  
Author(s):  
David A. Loewenstein ◽  
Ellen Amigo ◽  
Ranjan Duara ◽  
Andrew Guterman ◽  
Deborah Hurwitz ◽  
...  
Keyword(s):  
Functional Status ◽  
Direct Assessment

scholarly journals The Impact of the First 2020 COVID-19 Lockdown on the Metabolic Control of Patients with Phenylketonuria

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 2024
Author(s):  
Dariusz Walkowiak ◽  
Bożena Mikołuć ◽  
Renata Mozrzymas ◽  
Łukasz Kałużny ◽  
Bożena Didycz ◽  
...  
Keyword(s):  
Metabolic Control ◽  
P Value ◽  
Blood Tests ◽  
Direct Assessment ◽  
Blood Phenylalanine ◽  
The Impact

The present study assessed patients’ metabolic control of phenylketonuria (PKU) during the first 2020 COVID-19 lockdown in Poland. Blood (phenylalanine) Phe results of the tests of 535 patients, performed in 2019 and in the first months of 2020, were analysed. The six-week lockdown period was compared to the preceding six-week period as well as to the two corresponding periods of 2019 (three non-lockdown periods). More patients failed to perform Phe tests in the lockdown period (32.7%) than in non-lockdown periods (15.6%, 15.1%, 17.2%; p < 0.001 for all). The median Phe levels for those patients who performed testing in all the four periods did not differ between periods. However, these patients tended to perform only one test during the lockdown (ORs: 1.43 to 1.60; 95% CI: from 1.01–2.04 to 1.11–2.30, p-value 0.02 to 0.005). Patients who did not take blood during the lockdown (46.7%) performed significantly fewer blood tests in the remaining periods (median <IQR>: 1 <0–1> vs. 2 <1–4>; p < 0.001). In conclusion, direct assessment of patients’ compliance based upon Phe levels during the pandemic lockdown was not possible. Pre-pandemic non-compliant patients frequently failed to perform the test during the lockdown, whereas the previously compliant ones were more likely to perform only one test. This strongly suggests that metabolic control might have worsened.

scholarly journals Investigating the Effects of Surface Adsorbates on Gold and Palladium Deposition on Carbon

2021 ◽  
Author(s):  
Bethany Bowden ◽  
Josh A. Davies-Jones ◽  
Matthew Davies ◽  
Philip R. Davies ◽  
David J. Morgan ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Ammonium Hydroxide ◽  
Ammonium Ion ◽  
Metallic State ◽  
Chloroauric Acid ◽  
Final State ◽  
Ammonium Thiosulfate ◽  
Surface Adsorbates ◽  
Surface Hydroxyls ◽  
High Concentrations

AbstractSurface functional groups have a strong influence on the deposition and final state of nanoparticles adsorbed on to the surface, a role discussed by Professor Spencer in his work. This tribute to Spencer explores the formation of hydroxyls, thiosulfates, sulfites and sulfur atoms on carbon (HOPG) surfaces and their effect on the deposition of gold and palladium from aqueous solutions. Hydroxyls formed from ammonium hydroxide treatment have identical behaviour to those formed by acid treatment, and gold adsorption from Au3+ solutions gives Au0 initially, with Au3+ formed at higher concentrations on these surfaces. In contrast, palladium adsorption is hindered by the presence of the hydroxyls and there is no indication of any reduction to the metallic state. Ammonium thiosulfate adsorbs dissociatively from aqueous solutions on HOPG if the surface is pre-activated by the presence of surface hydroxyls. At low concentrations of ammonium thiosulfate, adsorbed sulfite and sulfur are formed in equimolar concentrations whereas adsorption of high concentrations of ammonium thiosulfate gives some degree of molecular adsorption, with evidence in XP spectra for an ammonium ion and a sulfur 2p peak at 282.9 eV attributed to the undissociated thiosulfate ion. Both sulfur and the sulfite are stable at the surface in neutral solutions but the sulfite desorbs when treated with acidified solutions (~ pH ≤ 6). These two groups are also stable at 373 K but begin to desorb by 473 K. Exposure to a weak chloroauric acid solution causes the desorption of the sulfite and formation of a gold species with an XP binding energy of 84.6 eV; we cannot determine from the present data whether this peak is due to a Au(I) state or very small nanoparticles of Au(0). Graphic Abstract

Pipeline Corrosion Integrity Management by Direct Assessment

2015 ◽  
Author(s):  
Shailesh Javia
Keyword(s):  
Integrated Approach ◽  
Assessment Process ◽  
Regulatory Requirements ◽  
Integrity Assessment ◽  
Advantages And Disadvantages ◽  
Direct Assessment ◽  
Pipeline Segment ◽  
Integrity Management ◽  
Post Assessment ◽  
Pipeline Corrosion

Integrity management of pipelines is a systematic, comprehensive and integrated approach to proactively counter the threats to pipeline integrity. Pressure testing, in-line inspection and direct assessment methods are used to verify the integrity of a buried pipeline. The Paper Discuses Direct Assessment Methodologies for Hydrocarbon Non Piggable Pipelines. Advantages and Disadvantages of Direct Assessment methodology and DA Protocols. The DA process accomplishes this by utilizing and integrating condition monitoring, effective mitigation, meticulous documentation and timely structured reporting processes. DA is a structured, iterative integrity assessment process through which an operator may be able to assess and evaluate the integrity of a pipeline segment. TIME DEPENDENT THREATS INEVITABLY LED TO NUMEROUS FAILURES WITH A COMMON DEFINING MECHANISM OR SOURCE – CORROSION. This Paper will focus on internal, external and stress corrosion cracking direct assessment along with pre and post assessment, quality assurance, data analysis and integration, and remediation and mitigation activities. This paper will discuss some of the regulatory requirements for Pipeline Integrity Management System.

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